【摘要】 聚合反应过程的热量管理是影响聚合物品质以及工程放大成败的关键因素之一.本文通过在PPTA聚合过程中引入液氮,考察了PPTA在传统低温溶液缩聚法制备过程中,采用惰性传热介质液氮作为辅助移热介质时,对PPTA聚合过程及聚合物性能的影响.结果表明,在PPTA聚合过程中适量液氮的加入可提高其比浓对数黏度和热稳定性,改善PPTA的表面浸润性能,并且未对PPTA的化学结构、聚集态结构及液晶形态产生明显影响.在140,300及1000 L反应釜的聚合放大实验中所得聚合物的比浓对数黏度均在6 d L/g以上.更多还原

【Abstract】 Thermal management of the polymerization reaction process is one of key factors influencing polymer quality and success in engineering scale-up. Liquid nitrogen is introduced in PPTA polymerization process in the paper, so as to investigate influence on PPTA polymerization process and polymer performance when the inertia heat transfer medium of liquid nitrogen is adopted as the auxiliary heat transfer medium during polycondensation of traditional cryogenic fluid. It is indicated from results that addition of proper amount of liquid nitrogen during PPTA polymerization process can improve logarithmic viscosity and thermal stability, and improve the surface wettability of PPTA. It will not cause obvious influence on the chemical structure, aggregation structure and liquid crystal pattern of PPTA. The logarithmic viscosities of polymer obtained from the polymerization scale-up experiment of 140, 300 and 1000 L reaction vessels are above 6 dL /g更多还原